1. Field of the Invention
The present invention relates to a direct cooling type refrigerator, and more particularly, to a direct cooling type refrigerator that is capable of improving a refrigerating performance of a refrigerating chamber and capable of minimizing a temperature change in the refrigerating chamber.
2. Description of the Background Art
In general, a refrigerator is sectioned into a freezing chamber for keeping frozen food items and a refrigerating chamber for keeping refrigerated food items, and includes a freezing cycle to supply cooling air to the freezing chamber and the refrigerating chamber therein.
The refrigerator is classified into a direct cooling type refrigerator of natural convection in which air inside a refrigerator and an evaporator directly come in contact with to perform a cooling operation, and an indirect cooling type refrigerator in which a duct for flowing cooling air is formed inside a refrigerator and the cooling air is blown into the refrigerator by a blast fan to thereby perform a cooling operation.
The direct cooling type refrigerator is mainly used for a small-size refrigerator with a small capacity, while the indirect cooling type refrigerator is mainly used for a large scale refrigerator with a large capacity.
FIG. 1 is a sectional view of the direct cooling type refrigerator in accordance with the background art.
The direct cooling type refrigerator shown in FIG. 1 includes a main body 104 having a certain space for storing food items and having a door 102 (not shown) mounted to be opened and closed at an opened front side of the main body 104; a freezing chamber 106 formed at an upper side of the main body 104 and storing frozen food items; a refrigerating chamber 108 partitioned with the freezing chamber 106 by a barrier 110 and formed at a lower portion of the main body 104 to store refrigerated food items; and a freezing cycle containing an evaporator 112 buried in the side wall of the freezing chamber 106 and performing a cooling operation by directly contacting the air inside the freezing chamber 106.
The freezing chamber 106 is formed at an upper portion of the main body 104, and a refrigerating chamber door 114 is separately installed at an opened front side of the main body 104.
The barrier 110 is installed between the refrigerating chamber 108 and the freezing chamber 106, and a plurality of shelves 128 are mounted in the refrigerating chamber 108 at regular intervals to receive food items.
The barrier 110 is formed as a tray type detachably mounted at one side of the main body 104, and has a plurality of cooling air supply passages 116 for supplying cooling air generated from the freezing chamber 106 to the refrigerating chamber 108.
The evaporator 112 is buried inside at least one of the side walls, e.g., a side wall other than the opening side where the refrigerating chamber door 114 is mounted over the refrigerating chamber 106, and in direct contact with air inside the freezing chamber 106 to perform a cooling operation.
A temperature sensor 118 is attached at one side of the evaporator 112 to detect a temperature of the freezing chamber 106 to turn on/off the freezing system.
As shown in FIG. 2, the freezing system of the background art includes a compressor 120 for raising a gas refrigerant in a low temperature and low pressure state to a gas coolant of high temperature and a high pressure; a condenser 122 for cooling and condensing the refrigerant in the high temperature and high pressure state introduced from the compressor 120 by an ambient air; an expansion valve 124 for decompressing the refrigerant introduced from the condenser 122; and an evaporator 112 for evaporating the refrigerant decompressed in the expansion valve 124 at the low pressure and low temperature state and allowing the refrigerant to directly contact the air of the freezing chamber 106 to thereby perform a cooling operation.
In the above-described direct cooling type refrigerator, as the freezing system is driven, the air inside the freezing chamber 106 comes in contact with the evaporator 112 to cool the freezing chamber 106, and after the cooling air completes the cooling operation while circulating the freezing chamber 106, the cooling air is supplied to the refrigerating chamber 108 through the cooling air supply passage 116 of the barrier 110 to perform a cooling operation of the refrigerating chamber 108.
However, the conventional direct cooling type refrigerator has the following problems.
That is, since the evaporator is installed only in the freezing chamber and the cooling air generated in the freezing chamber is supplied to the refrigerating chamber, the cooling performance of the refrigerating chamber is degraded, a cooling time for maintaining the temperature in the refrigerating chamber to a proper level increases, and the freshness of refrigerated food items kept in the refrigerating chamber is degraded.
Therefore, an object of the present invention is to provide a direct cooling type refrigerator that is capable of quickly dropping a temperature of a refrigerating chamber to a suitable level and thus improving freshness of refrigerated food items kept in the refrigerating chamber by installing an evaporator in the refrigerating chamber as well as in a freezing chamber to make a heat exchange with air inside the refrigerating chamber.
Another object of the present invention is to provide a direct cooling type refrigerator that is capable of improving an efficiency of a freezing cycle and reducing a power consumption by attaching a temperature sensor to an evaporator installed in a freezing chamber to control a system.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided a direct cooling type refrigerator including: a main body with a certain space for keeping food items; a freezing chamber formed at an upper portion of the main body and keeping frozen food items; a refrigerating chamber sectioned by a barrier with the freezing chamber, formed at a lower portion of the main body and keeping refrigerated food items; a freezing chamber evaporator buried in a side wall of the freezing chamber and directly heat-exchanged with air inside the freezing chamber; and a refrigerating chamber evaporator buried in a side wall of the refrigerating chamber and directly heat-exchanged with air inside the refrigerating chamber.
The direct cooling type refrigerator of the present invention further includes: a temperature sensor attached to the freezing chamber evaporator and detecting a temperature of the freezing chamber; and a control unit for turning off/off a freezing cycle of a refrigerator so that the temperature of the freezing chamber and the refrigerating chamber can be maintained at a suitable level according to an electric signal applied from the temperature sensor
In the direct cooling type refrigerator of the present invention, the refrigerating chamber evaporator is formed as a flat plate type buried in a rear wall of the refrigerating chamber.
In the direct cooling type refrigerator of the present invention, the refrigerating chamber evaporator is formed as a bent flat plate type integrally buried in a rear wall and left and right side walls of the refrigerating chamber.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.